微量Zr对铸造TiAl合金高温力学性能的影响  

Effects of Trace Zirconium Addition on High Temperature Mechanical Properties of Casting TiAl Alloy

作　　者：骆晨[1] 吕楠[2] 朱春雷[1] 李海昭[1] 柳学全[1] 

机构地区：[1]钢铁研究总院高温材料研究所,北京100081 [2]辽宁科技大学材料与冶金学院,辽宁沈阳114051

出　　处：《铸造》2012年第7期754-757,共4页Foundry

摘　　要：在Ti-47.5Al-2.5V-1.0Cr合金中添加0.2at.%Zr以研究微量Zr对铸造形成的定向层片组织高温力学性能的作用。结果表明,添加0.2at.%Zr显著提高了该合金的持久寿命,但未对其高温拉伸强度产生明显影响。根据两种合金持久试验前后组织对比观察的结果提出,添加微量Zr主要是通过增加定向层片组织的热稳定性而使其持久性能得以改善;另外,微量Zr减少了热等静压过程中等轴晶粒的析出,也有助于延长合金的持久寿命。Based on directional lamellar microstructure of Ti-47.5Al-2.5V-1.0Cr （at.%） alloy by adding 0.2at.% Zr, the effects of trace zirconium on high temperature mechanical properties of cast TiA1 alloy have been studied. The result shows that adding 0.2at.% Zr significantly increased the creep rupture life of the alloy, but did not influence the high temperature tensile strength obviously. According to examination on the microstructures of alloys before and after test, the mainly reason that trace Zr increased the rupture life is that Zr improves the lamella thermal stability of cast TiA1 alloy. Additionally, Zr hinders the precipitation of equiaxed gamma grain during hot isostatic pressing, which is also beneficial to creep rupture properties.

关 键 词：铸造TIAL合金 定向层片组织 微量Zr 高温力学性能 

分 类 号：TG292[金属学及工艺—铸造]